Error messages in PDF conversion (using DocBook stylesheets)

["Derek Hohls" <DHohls@csir.co.za>]

I have managed to get reasonable HTML output from my DocBook docs, 
using the DocBook stylesheets.

I am now on the (to my mind) more challenging task of trying to create

PDF output.  I have successfully run the XML -> FO -> PDF using FOP 
(using the default stylesheet with no special options); but the
generation 
process reports a number of "errors" along the way.  For example; 

[ERROR] property - "background-position-horizontal" is not implemented
yet.
[ERROR] property - "background-position-vertical" is not implemented
yet.
Error creating background image: Error while recovering Image
Informations (http:
ge.net/release/images/draft.png) : Operation timed out: no further
information

gets reported a number of times, as does:

[ERROR] Unknown enumerated value for property 'relative-align':
baseline
[ERROR] Error in relative-align property value 'baseline':
org.apache.fop.fo.expr.PropertyException:
 No conversion defined

and, right near the end:

[ERROR] At least one of minimum, optimum, or maximum IPD must be
specified on table.

The output document is created OK, so I guess these are more in the 
form of warnings - but is there any way to remove these messages 
from the generation process - or is there a root cause I should be 
worried about??

Thanks
Derek

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